The National Restaurant Association's Restaurant Performance Index (RPI) declined for the third consecutive month. The RPI — a monthly composite index that tracks the health of and outlook for the U.S. restaurant industry — stood at 100.5 in August, down 0.2 percent from July's level of 100.7. Despite the recent declines, the RPI remained above 100 for the sixth consecutive month, which signifies expansion in the index of key industry indicators.

The Current Situation Index, which measures current trends in four industry indicators (same-store sales, traffic, labor and capital expenditures), stood at 100.7 in August — up 0.6 percent from July and the first increase in three months. In addition, the Current Situation Index stood above 100 for the fifth consecutive month, which signifies expansion in the current situation indicators.

A majority of restaurant operators reported positive same-store sales in August, and the overall results were an improvement over July's performance. Key data points from the Current Situation Index include:

Fifty-three percent of restaurant operators reported a same-store sales gain between August 2012 and August 2013, up from 44 percent who reported higher sales in July. In comparison, 33 percent of operators reported a decline in same-store sales in August, down slightly from 36 percent in July.

Forty-five percent of restaurant operators reported higher customer traffic levels between August 2012 and August 2013, up from 35 percent who reported a traffic gain in July. Meanwhile, 38 percent of operators reported a decline in customer traffic in August, down from 43 percent in July.

Fifty-three percent of operators said they made a capital expenditure for equipment, expansion or remodeling during the last three months, the fourth consecutive month in which a majority of operators reported expenditures.

The Expectations Index, which measures restaurant operators' six-month outlook for four industry indicators (same-store sales, employees, capital expenditures and business conditions), stood at 100.4 in August – down 0.9 percent from July and the lowest level in eight months. Key data points from the Expectations Index include:

Thirty-six percent of restaurant operators expect to have higher sales in six months (compared to the same period in the previous year), down slightly from 37 percent last month and the lowest level in 10 months. Meanwhile, 16 percent of restaurant operators expect their sales volume in six months to be lower than it was during the same period in the previous year, up from 9 percent last month and the highest level in seven months.

Twenty-three percent of restaurant operators said they expect economic conditions to improve in six months, unchanged from last month. However, 22 percent of operators said they expect economic conditions to worsen in the next six months, up from 18 percent last month and the highest level in eight months.

Forty-five percent of restaurant operators plan to make a capital expenditure for equipment, expansion or remodeling in the next six months, down from 53 percent who reported similarly last month.